A function is satisfiable if there exists an assignment of 1s and 0 s to the variables that makes the function evaluate to 1 . Are the following functions satisfiable? If the function is satisfiable, list the values of the variables which make the function satisfiable. Please give your solution in a single line containing 4 comma-separated values, each of which is either 0 or 1 (in the order: x,y,z,v). For example, you would submit 1,0,1,0, if the function is satisfiable with x=0,y=0,z=1, and v=0. If the function is not satisfiable, use the laws of boolean algebra to prove that the function is a contradiction, i.e. show that regardless of the assignments to the variables, the function will always evaluate to 0 . b) z(z+x)(y+v)(z+x) c) (x+y)(z+v)(y+x)(xy) d) xv(y+x)(z+x)